2 -- ---------------------------------------------------------------------------
3 -- (c) The University of Glasgow 1997-2003
7 -- Author(s): Simon Marlow, Sven Panne 1997, 1998, 1999
8 -- ---------------------------------------------------------------------------
11 {-# OPTIONS -Wwarn -w #-}
12 -- The above warning supression flag is a temporary kludge.
13 -- While working on this module you are encouraged to remove it and fix
14 -- any warnings in the module. See
15 -- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
18 {-# OPTIONS_GHC -O0 -fno-ignore-interface-pragmas #-}
20 Careful optimisation of the parser: we don't want to throw everything
21 at it, because that takes too long and doesn't buy much, but we do want
22 to inline certain key external functions, so we instruct GHC not to
23 throw away inlinings as it would normally do in -O0 mode.
26 module Parser ( parseModule, parseStmt, parseIdentifier, parseType,
31 import HscTypes ( IsBootInterface, WarningTxt(..) )
34 import TysWiredIn ( unitTyCon, unitDataCon, tupleTyCon, tupleCon, nilDataCon,
35 unboxedSingletonTyCon, unboxedSingletonDataCon,
36 listTyCon_RDR, parrTyCon_RDR, consDataCon_RDR )
37 import Type ( funTyCon )
38 import ForeignCall ( Safety(..), CExportSpec(..), CLabelString,
39 CCallConv(..), CCallTarget(..), defaultCCallConv
41 import OccName ( varName, dataName, tcClsName, tvName )
42 import DataCon ( DataCon, dataConName )
43 import SrcLoc ( Located(..), unLoc, getLoc, noLoc, combineSrcSpans,
44 SrcSpan, combineLocs, srcLocFile,
47 import StaticFlags ( opt_SccProfilingOn, opt_Hpc )
48 import Type ( Kind, mkArrowKind, liftedTypeKind, unliftedTypeKind )
49 import Class ( FunDep )
50 import BasicTypes ( Boxity(..), Fixity(..), FixityDirection(..), IPName(..),
51 Activation(..), RuleMatchInfo(..), defaultInlineSpec )
55 import {-# SOURCE #-} HaddockLex hiding ( Token )
59 import Maybes ( orElse )
62 import Control.Monad ( unless )
65 import Control.Monad ( mplus )
69 -----------------------------------------------------------------------------
72 Conflicts: 33 shift/reduce
75 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
76 would think the two should never occur in the same context.
80 -----------------------------------------------------------------------------
83 Conflicts: 34 shift/reduce
86 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
87 would think the two should never occur in the same context.
91 -----------------------------------------------------------------------------
94 Conflicts: 32 shift/reduce
97 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
98 would think the two should never occur in the same context.
102 -----------------------------------------------------------------------------
105 Conflicts: 37 shift/reduce
108 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
109 would think the two should never occur in the same context.
113 -----------------------------------------------------------------------------
114 Conflicts: 38 shift/reduce (1.25)
116 10 for abiguity in 'if x then y else z + 1' [State 178]
117 (shift parses as 'if x then y else (z + 1)', as per longest-parse rule)
118 10 because op might be: : - ! * . `x` VARSYM CONSYM QVARSYM QCONSYM
120 1 for ambiguity in 'if x then y else z :: T' [State 178]
121 (shift parses as 'if x then y else (z :: T)', as per longest-parse rule)
123 4 for ambiguity in 'if x then y else z -< e' [State 178]
124 (shift parses as 'if x then y else (z -< T)', as per longest-parse rule)
125 There are four such operators: -<, >-, -<<, >>-
128 2 for ambiguity in 'case v of { x :: T -> T ... } ' [States 11, 253]
129 Which of these two is intended?
131 (x::T) -> T -- Rhs is T
134 (x::T -> T) -> .. -- Rhs is ...
136 10 for ambiguity in 'e :: a `b` c'. Does this mean [States 11, 253]
139 As well as `b` we can have !, VARSYM, QCONSYM, and CONSYM, hence 5 cases
140 Same duplication between states 11 and 253 as the previous case
142 1 for ambiguity in 'let ?x ...' [State 329]
143 the parser can't tell whether the ?x is the lhs of a normal binding or
144 an implicit binding. Fortunately resolving as shift gives it the only
145 sensible meaning, namely the lhs of an implicit binding.
147 1 for ambiguity in '{-# RULES "name" [ ... #-} [State 382]
148 we don't know whether the '[' starts the activation or not: it
149 might be the start of the declaration with the activation being
150 empty. --SDM 1/4/2002
152 1 for ambiguity in '{-# RULES "name" forall = ... #-}' [State 474]
153 since 'forall' is a valid variable name, we don't know whether
154 to treat a forall on the input as the beginning of a quantifier
155 or the beginning of the rule itself. Resolving to shift means
156 it's always treated as a quantifier, hence the above is disallowed.
157 This saves explicitly defining a grammar for the rule lhs that
158 doesn't include 'forall'.
160 1 for ambiguity when the source file starts with "-- | doc". We need another
161 token of lookahead to determine if a top declaration or the 'module' keyword
162 follows. Shift parses as if the 'module' keyword follows.
164 -- ---------------------------------------------------------------------------
165 -- Adding location info
167 This is done in a stylised way using the three macros below, L0, L1
168 and LL. Each of these macros can be thought of as having type
170 L0, L1, LL :: a -> Located a
172 They each add a SrcSpan to their argument.
174 L0 adds 'noSrcSpan', used for empty productions
175 -- This doesn't seem to work anymore -=chak
177 L1 for a production with a single token on the lhs. Grabs the SrcSpan
180 LL for a production with >1 token on the lhs. Makes up a SrcSpan from
181 the first and last tokens.
183 These suffice for the majority of cases. However, we must be
184 especially careful with empty productions: LL won't work if the first
185 or last token on the lhs can represent an empty span. In these cases,
186 we have to calculate the span using more of the tokens from the lhs, eg.
188 | 'newtype' tycl_hdr '=' newconstr deriving
190 (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
192 We provide comb3 and comb4 functions which are useful in such cases.
194 Be careful: there's no checking that you actually got this right, the
195 only symptom will be that the SrcSpans of your syntax will be
199 * We must expand these macros *before* running Happy, which is why this file is
200 * Parser.y.pp rather than just Parser.y - we run the C pre-processor first.
202 #define L0 L noSrcSpan
203 #define L1 sL (getLoc $1)
204 #define LL sL (comb2 $1 $>)
206 -- -----------------------------------------------------------------------------
211 '_' { L _ ITunderscore } -- Haskell keywords
213 'case' { L _ ITcase }
214 'class' { L _ ITclass }
215 'data' { L _ ITdata }
216 'default' { L _ ITdefault }
217 'deriving' { L _ ITderiving }
219 'else' { L _ ITelse }
220 'hiding' { L _ IThiding }
222 'import' { L _ ITimport }
224 'infix' { L _ ITinfix }
225 'infixl' { L _ ITinfixl }
226 'infixr' { L _ ITinfixr }
227 'instance' { L _ ITinstance }
229 'module' { L _ ITmodule }
230 'newtype' { L _ ITnewtype }
232 'qualified' { L _ ITqualified }
233 'then' { L _ ITthen }
234 'type' { L _ ITtype }
235 'where' { L _ ITwhere }
236 '_scc_' { L _ ITscc } -- ToDo: remove
238 'forall' { L _ ITforall } -- GHC extension keywords
239 'foreign' { L _ ITforeign }
240 'export' { L _ ITexport }
241 'label' { L _ ITlabel }
242 'dynamic' { L _ ITdynamic }
243 'safe' { L _ ITsafe }
244 'threadsafe' { L _ ITthreadsafe } -- ToDo: remove deprecated alias
245 'unsafe' { L _ ITunsafe }
247 'family' { L _ ITfamily }
248 'stdcall' { L _ ITstdcallconv }
249 'ccall' { L _ ITccallconv }
250 'prim' { L _ ITprimcallconv }
251 'proc' { L _ ITproc } -- for arrow notation extension
252 'rec' { L _ ITrec } -- for arrow notation extension
253 'group' { L _ ITgroup } -- for list transform extension
254 'by' { L _ ITby } -- for list transform extension
255 'using' { L _ ITusing } -- for list transform extension
257 '{-# INLINE' { L _ (ITinline_prag _) }
258 '{-# INLINE_CONLIKE' { L _ (ITinline_conlike_prag _) }
259 '{-# SPECIALISE' { L _ ITspec_prag }
260 '{-# SPECIALISE_INLINE' { L _ (ITspec_inline_prag _) }
261 '{-# SOURCE' { L _ ITsource_prag }
262 '{-# RULES' { L _ ITrules_prag }
263 '{-# CORE' { L _ ITcore_prag } -- hdaume: annotated core
264 '{-# SCC' { L _ ITscc_prag }
265 '{-# GENERATED' { L _ ITgenerated_prag }
266 '{-# DEPRECATED' { L _ ITdeprecated_prag }
267 '{-# WARNING' { L _ ITwarning_prag }
268 '{-# UNPACK' { L _ ITunpack_prag }
269 '{-# ANN' { L _ ITann_prag }
270 '#-}' { L _ ITclose_prag }
272 '..' { L _ ITdotdot } -- reserved symbols
274 '::' { L _ ITdcolon }
278 '<-' { L _ ITlarrow }
279 '->' { L _ ITrarrow }
282 '=>' { L _ ITdarrow }
286 '-<' { L _ ITlarrowtail } -- for arrow notation
287 '>-' { L _ ITrarrowtail } -- for arrow notation
288 '-<<' { L _ ITLarrowtail } -- for arrow notation
289 '>>-' { L _ ITRarrowtail } -- for arrow notation
292 '{' { L _ ITocurly } -- special symbols
294 '{|' { L _ ITocurlybar }
295 '|}' { L _ ITccurlybar }
296 vocurly { L _ ITvocurly } -- virtual open curly (from layout)
297 vccurly { L _ ITvccurly } -- virtual close curly (from layout)
300 '[:' { L _ ITopabrack }
301 ':]' { L _ ITcpabrack }
304 '(#' { L _ IToubxparen }
305 '#)' { L _ ITcubxparen }
306 '(|' { L _ IToparenbar }
307 '|)' { L _ ITcparenbar }
310 '`' { L _ ITbackquote }
312 VARID { L _ (ITvarid _) } -- identifiers
313 CONID { L _ (ITconid _) }
314 VARSYM { L _ (ITvarsym _) }
315 CONSYM { L _ (ITconsym _) }
316 QVARID { L _ (ITqvarid _) }
317 QCONID { L _ (ITqconid _) }
318 QVARSYM { L _ (ITqvarsym _) }
319 QCONSYM { L _ (ITqconsym _) }
320 PREFIXQVARSYM { L _ (ITprefixqvarsym _) }
321 PREFIXQCONSYM { L _ (ITprefixqconsym _) }
323 IPDUPVARID { L _ (ITdupipvarid _) } -- GHC extension
325 CHAR { L _ (ITchar _) }
326 STRING { L _ (ITstring _) }
327 INTEGER { L _ (ITinteger _) }
328 RATIONAL { L _ (ITrational _) }
330 PRIMCHAR { L _ (ITprimchar _) }
331 PRIMSTRING { L _ (ITprimstring _) }
332 PRIMINTEGER { L _ (ITprimint _) }
333 PRIMWORD { L _ (ITprimword _) }
334 PRIMFLOAT { L _ (ITprimfloat _) }
335 PRIMDOUBLE { L _ (ITprimdouble _) }
337 DOCNEXT { L _ (ITdocCommentNext _) }
338 DOCPREV { L _ (ITdocCommentPrev _) }
339 DOCNAMED { L _ (ITdocCommentNamed _) }
340 DOCSECTION { L _ (ITdocSection _ _) }
343 '[|' { L _ ITopenExpQuote }
344 '[p|' { L _ ITopenPatQuote }
345 '[t|' { L _ ITopenTypQuote }
346 '[d|' { L _ ITopenDecQuote }
347 '|]' { L _ ITcloseQuote }
348 TH_ID_SPLICE { L _ (ITidEscape _) } -- $x
349 '$(' { L _ ITparenEscape } -- $( exp )
350 TH_VAR_QUOTE { L _ ITvarQuote } -- 'x
351 TH_TY_QUOTE { L _ ITtyQuote } -- ''T
352 TH_QUASIQUOTE { L _ (ITquasiQuote _) }
354 %monad { P } { >>= } { return }
355 %lexer { lexer } { L _ ITeof }
356 %name parseModule module
357 %name parseStmt maybe_stmt
358 %name parseIdentifier identifier
359 %name parseType ctype
360 %partial parseHeader header
361 %tokentype { (Located Token) }
364 -----------------------------------------------------------------------------
365 -- Identifiers; one of the entry points
366 identifier :: { Located RdrName }
371 | '(' '->' ')' { LL $ getRdrName funTyCon }
373 -----------------------------------------------------------------------------
376 -- The place for module deprecation is really too restrictive, but if it
377 -- was allowed at its natural place just before 'module', we get an ugly
378 -- s/r conflict with the second alternative. Another solution would be the
379 -- introduction of a new pragma DEPRECATED_MODULE, but this is not very nice,
380 -- either, and DEPRECATED is only expected to be used by people who really
381 -- know what they are doing. :-)
383 module :: { Located (HsModule RdrName) }
384 : maybedocheader 'module' modid maybemodwarning maybeexports 'where' body
385 {% fileSrcSpan >>= \ loc -> case $1 of { (info, doc) ->
386 return (L loc (HsModule (Just $3) $5 (fst $7) (snd $7) $4
389 {% fileSrcSpan >>= \ loc ->
390 return (L loc (HsModule Nothing Nothing
391 (fst $1) (snd $1) Nothing emptyHaddockModInfo
394 maybedocheader :: { (HaddockModInfo RdrName, Maybe (HsDoc RdrName)) }
395 : moduleheader { $1 }
396 | {- empty -} { (emptyHaddockModInfo, Nothing) }
398 missing_module_keyword :: { () }
399 : {- empty -} {% pushCurrentContext }
401 maybemodwarning :: { Maybe WarningTxt }
402 : '{-# DEPRECATED' strings '#-}' { Just (DeprecatedTxt $ unLoc $2) }
403 | '{-# WARNING' strings '#-}' { Just (WarningTxt $ unLoc $2) }
404 | {- empty -} { Nothing }
406 body :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
408 | vocurly top close { $2 }
410 body2 :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
412 | missing_module_keyword top close { $2 }
414 top :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
415 : importdecls { (reverse $1,[]) }
416 | importdecls ';' cvtopdecls { (reverse $1,$3) }
417 | cvtopdecls { ([],$1) }
419 cvtopdecls :: { [LHsDecl RdrName] }
420 : topdecls { cvTopDecls $1 }
422 -----------------------------------------------------------------------------
423 -- Module declaration & imports only
425 header :: { Located (HsModule RdrName) }
426 : maybedocheader 'module' modid maybemodwarning maybeexports 'where' header_body
427 {% fileSrcSpan >>= \ loc -> case $1 of { (info, doc) ->
428 return (L loc (HsModule (Just $3) $5 $7 [] $4
430 | missing_module_keyword importdecls
431 {% fileSrcSpan >>= \ loc ->
432 return (L loc (HsModule Nothing Nothing $2 [] Nothing
433 emptyHaddockModInfo Nothing)) }
435 header_body :: { [LImportDecl RdrName] }
436 : '{' importdecls { $2 }
437 | vocurly importdecls { $2 }
439 -----------------------------------------------------------------------------
442 maybeexports :: { Maybe [LIE RdrName] }
443 : '(' exportlist ')' { Just $2 }
444 | {- empty -} { Nothing }
446 exportlist :: { [LIE RdrName] }
447 : expdoclist ',' expdoclist { $1 ++ $3 }
450 exportlist1 :: { [LIE RdrName] }
451 : expdoclist export expdoclist ',' exportlist { $1 ++ ($2 : $3) ++ $5 }
452 | expdoclist export expdoclist { $1 ++ ($2 : $3) }
455 expdoclist :: { [LIE RdrName] }
456 : exp_doc expdoclist { $1 : $2 }
459 exp_doc :: { LIE RdrName }
460 : docsection { L1 (case (unLoc $1) of (n, doc) -> IEGroup n doc) }
461 | docnamed { L1 (IEDocNamed ((fst . unLoc) $1)) }
462 | docnext { L1 (IEDoc (unLoc $1)) }
464 -- No longer allow things like [] and (,,,) to be exported
465 -- They are built in syntax, always available
466 export :: { LIE RdrName }
467 : qvar { L1 (IEVar (unLoc $1)) }
468 | oqtycon { L1 (IEThingAbs (unLoc $1)) }
469 | oqtycon '(' '..' ')' { LL (IEThingAll (unLoc $1)) }
470 | oqtycon '(' ')' { LL (IEThingWith (unLoc $1) []) }
471 | oqtycon '(' qcnames ')' { LL (IEThingWith (unLoc $1) (reverse $3)) }
472 | 'module' modid { LL (IEModuleContents (unLoc $2)) }
474 qcnames :: { [RdrName] }
475 : qcnames ',' qcname_ext { unLoc $3 : $1 }
476 | qcname_ext { [unLoc $1] }
478 qcname_ext :: { Located RdrName } -- Variable or data constructor
479 -- or tagged type constructor
481 | 'type' qcon { sL (comb2 $1 $2)
482 (setRdrNameSpace (unLoc $2)
485 -- Cannot pull into qcname_ext, as qcname is also used in expression.
486 qcname :: { Located RdrName } -- Variable or data constructor
490 -----------------------------------------------------------------------------
491 -- Import Declarations
493 -- import decls can be *empty*, or even just a string of semicolons
494 -- whereas topdecls must contain at least one topdecl.
496 importdecls :: { [LImportDecl RdrName] }
497 : importdecls ';' importdecl { $3 : $1 }
498 | importdecls ';' { $1 }
499 | importdecl { [ $1 ] }
502 importdecl :: { LImportDecl RdrName }
503 : 'import' maybe_src optqualified maybe_pkg modid maybeas maybeimpspec
504 { L (comb4 $1 $5 $6 $7) (ImportDecl $5 $4 $2 $3 (unLoc $6) (unLoc $7)) }
506 maybe_src :: { IsBootInterface }
507 : '{-# SOURCE' '#-}' { True }
508 | {- empty -} { False }
510 maybe_pkg :: { Maybe FastString }
511 : STRING { Just (getSTRING $1) }
512 | {- empty -} { Nothing }
514 optqualified :: { Bool }
515 : 'qualified' { True }
516 | {- empty -} { False }
518 maybeas :: { Located (Maybe ModuleName) }
519 : 'as' modid { LL (Just (unLoc $2)) }
520 | {- empty -} { noLoc Nothing }
522 maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
523 : impspec { L1 (Just (unLoc $1)) }
524 | {- empty -} { noLoc Nothing }
526 impspec :: { Located (Bool, [LIE RdrName]) }
527 : '(' exportlist ')' { LL (False, $2) }
528 | 'hiding' '(' exportlist ')' { LL (True, $3) }
530 -----------------------------------------------------------------------------
531 -- Fixity Declarations
535 | INTEGER {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
537 infix :: { Located FixityDirection }
538 : 'infix' { L1 InfixN }
539 | 'infixl' { L1 InfixL }
540 | 'infixr' { L1 InfixR }
542 ops :: { Located [Located RdrName] }
543 : ops ',' op { LL ($3 : unLoc $1) }
546 -----------------------------------------------------------------------------
547 -- Top-Level Declarations
549 topdecls :: { OrdList (LHsDecl RdrName) }
550 : topdecls ';' topdecl { $1 `appOL` $3 }
551 | topdecls ';' { $1 }
554 topdecl :: { OrdList (LHsDecl RdrName) }
555 : cl_decl { unitOL (L1 (TyClD (unLoc $1))) }
556 | ty_decl { unitOL (L1 (TyClD (unLoc $1))) }
557 | 'instance' inst_type where_inst
558 { let (binds, sigs, ats, _) = cvBindsAndSigs (unLoc $3)
560 unitOL (L (comb3 $1 $2 $3) (InstD (InstDecl $2 binds sigs ats)))}
561 | stand_alone_deriving { unitOL (LL (DerivD (unLoc $1))) }
562 | 'default' '(' comma_types0 ')' { unitOL (LL $ DefD (DefaultDecl $3)) }
563 | 'foreign' fdecl { unitOL (LL (unLoc $2)) }
564 | '{-# DEPRECATED' deprecations '#-}' { $2 }
565 | '{-# WARNING' warnings '#-}' { $2 }
566 | '{-# RULES' rules '#-}' { $2 }
567 | annotation { unitOL $1 }
570 -- Template Haskell Extension
571 | '$(' exp ')' { unitOL (LL $ SpliceD (SpliceDecl $2)) }
572 | TH_ID_SPLICE { unitOL (LL $ SpliceD (SpliceDecl $
573 L1 $ HsVar (mkUnqual varName (getTH_ID_SPLICE $1))
578 cl_decl :: { LTyClDecl RdrName }
579 : 'class' tycl_hdr fds where_cls {% mkClassDecl (comb4 $1 $2 $3 $4) $2 $3 $4 }
581 -- Type declarations (toplevel)
583 ty_decl :: { LTyClDecl RdrName }
584 -- ordinary type synonyms
585 : 'type' type '=' ctypedoc
586 -- Note ctype, not sigtype, on the right of '='
587 -- We allow an explicit for-all but we don't insert one
588 -- in type Foo a = (b,b)
589 -- Instead we just say b is out of scope
591 -- Note the use of type for the head; this allows
592 -- infix type constructors to be declared
593 {% mkTySynonym (comb2 $1 $4) False $2 $4 }
595 -- type family declarations
596 | 'type' 'family' type opt_kind_sig
597 -- Note the use of type for the head; this allows
598 -- infix type constructors to be declared
599 {% mkTyFamily (comb3 $1 $3 $4) TypeFamily $3 (unLoc $4) }
601 -- type instance declarations
602 | 'type' 'instance' type '=' ctype
603 -- Note the use of type for the head; this allows
604 -- infix type constructors and type patterns
605 {% mkTySynonym (comb2 $1 $5) True $3 $5 }
607 -- ordinary data type or newtype declaration
608 | data_or_newtype tycl_hdr constrs deriving
609 {% mkTyData (comb4 $1 $2 $3 $4) (unLoc $1) False $2
610 Nothing (reverse (unLoc $3)) (unLoc $4) }
611 -- We need the location on tycl_hdr in case
612 -- constrs and deriving are both empty
614 -- ordinary GADT declaration
615 | data_or_newtype tycl_hdr opt_kind_sig
616 'where' gadt_constrlist
618 {% mkTyData (comb4 $1 $2 $4 $5) (unLoc $1) False $2
619 (unLoc $3) (reverse (unLoc $5)) (unLoc $6) }
620 -- We need the location on tycl_hdr in case
621 -- constrs and deriving are both empty
623 -- data/newtype family
624 | 'data' 'family' type opt_kind_sig
625 {% mkTyFamily (comb3 $1 $2 $4) DataFamily $3 (unLoc $4) }
627 -- data/newtype instance declaration
628 | data_or_newtype 'instance' tycl_hdr constrs deriving
629 {% mkTyData (comb4 $1 $3 $4 $5) (unLoc $1) True $3
630 Nothing (reverse (unLoc $4)) (unLoc $5) }
632 -- GADT instance declaration
633 | data_or_newtype 'instance' tycl_hdr opt_kind_sig
634 'where' gadt_constrlist
636 {% mkTyData (comb4 $1 $3 $6 $7) (unLoc $1) True $3
637 (unLoc $4) (reverse (unLoc $6)) (unLoc $7) }
639 -- Associated type family declarations
641 -- * They have a different syntax than on the toplevel (no family special
644 -- * They also need to be separate from instances; otherwise, data family
645 -- declarations without a kind signature cause parsing conflicts with empty
646 -- data declarations.
648 at_decl_cls :: { LTyClDecl RdrName }
649 -- type family declarations
650 : 'type' type opt_kind_sig
651 -- Note the use of type for the head; this allows
652 -- infix type constructors to be declared
653 {% mkTyFamily (comb3 $1 $2 $3) TypeFamily $2 (unLoc $3) }
655 -- default type instance
656 | 'type' type '=' ctype
657 -- Note the use of type for the head; this allows
658 -- infix type constructors and type patterns
659 {% mkTySynonym (comb2 $1 $4) True $2 $4 }
661 -- data/newtype family declaration
662 | 'data' type opt_kind_sig
663 {% mkTyFamily (comb3 $1 $2 $3) DataFamily $2 (unLoc $3) }
665 -- Associated type instances
667 at_decl_inst :: { LTyClDecl RdrName }
668 -- type instance declarations
669 : 'type' type '=' ctype
670 -- Note the use of type for the head; this allows
671 -- infix type constructors and type patterns
672 {% mkTySynonym (comb2 $1 $4) True $2 $4 }
674 -- data/newtype instance declaration
675 | data_or_newtype tycl_hdr constrs deriving
676 {% mkTyData (comb4 $1 $2 $3 $4) (unLoc $1) True $2
677 Nothing (reverse (unLoc $3)) (unLoc $4) }
679 -- GADT instance declaration
680 | data_or_newtype tycl_hdr opt_kind_sig
681 'where' gadt_constrlist
683 {% mkTyData (comb4 $1 $2 $5 $6) (unLoc $1) True $2
684 (unLoc $3) (reverse (unLoc $5)) (unLoc $6) }
686 data_or_newtype :: { Located NewOrData }
687 : 'data' { L1 DataType }
688 | 'newtype' { L1 NewType }
690 opt_kind_sig :: { Located (Maybe Kind) }
692 | '::' kind { LL (Just (unLoc $2)) }
694 -- tycl_hdr parses the header of a class or data type decl,
695 -- which takes the form
698 -- (Eq a, Ord b) => T a b
699 -- T Int [a] -- for associated types
700 -- Rather a lot of inlining here, else we get reduce/reduce errors
701 tycl_hdr :: { Located (LHsContext RdrName, LHsType RdrName) }
702 : context '=>' type { LL ($1, $3) }
703 | type { L1 (noLoc [], $1) }
705 -----------------------------------------------------------------------------
706 -- Stand-alone deriving
708 -- Glasgow extension: stand-alone deriving declarations
709 stand_alone_deriving :: { LDerivDecl RdrName }
710 : 'deriving' 'instance' inst_type {% checkDerivDecl (LL (DerivDecl $3)) }
712 -----------------------------------------------------------------------------
713 -- Nested declarations
715 -- Declaration in class bodies
717 decl_cls :: { Located (OrdList (LHsDecl RdrName)) }
718 decl_cls : at_decl_cls { LL (unitOL (L1 (TyClD (unLoc $1)))) }
721 decls_cls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
722 : decls_cls ';' decl_cls { LL (unLoc $1 `appOL` unLoc $3) }
723 | decls_cls ';' { LL (unLoc $1) }
725 | {- empty -} { noLoc nilOL }
729 :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
730 : '{' decls_cls '}' { LL (unLoc $2) }
731 | vocurly decls_cls close { $2 }
735 where_cls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
736 -- No implicit parameters
737 -- May have type declarations
738 : 'where' decllist_cls { LL (unLoc $2) }
739 | {- empty -} { noLoc nilOL }
741 -- Declarations in instance bodies
743 decl_inst :: { Located (OrdList (LHsDecl RdrName)) }
744 decl_inst : at_decl_inst { LL (unitOL (L1 (TyClD (unLoc $1)))) }
747 decls_inst :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
748 : decls_inst ';' decl_inst { LL (unLoc $1 `appOL` unLoc $3) }
749 | decls_inst ';' { LL (unLoc $1) }
751 | {- empty -} { noLoc nilOL }
754 :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
755 : '{' decls_inst '}' { LL (unLoc $2) }
756 | vocurly decls_inst close { $2 }
760 where_inst :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
761 -- No implicit parameters
762 -- May have type declarations
763 : 'where' decllist_inst { LL (unLoc $2) }
764 | {- empty -} { noLoc nilOL }
766 -- Declarations in binding groups other than classes and instances
768 decls :: { Located (OrdList (LHsDecl RdrName)) }
769 : decls ';' decl { let { this = unLoc $3;
771 these = rest `appOL` this }
772 in rest `seq` this `seq` these `seq`
774 | decls ';' { LL (unLoc $1) }
776 | {- empty -} { noLoc nilOL }
778 decllist :: { Located (OrdList (LHsDecl RdrName)) }
779 : '{' decls '}' { LL (unLoc $2) }
780 | vocurly decls close { $2 }
782 -- Binding groups other than those of class and instance declarations
784 binds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
785 -- No type declarations
786 : decllist { L1 (HsValBinds (cvBindGroup (unLoc $1))) }
787 | '{' dbinds '}' { LL (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
788 | vocurly dbinds close { L (getLoc $2) (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
790 wherebinds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
791 -- No type declarations
792 : 'where' binds { LL (unLoc $2) }
793 | {- empty -} { noLoc emptyLocalBinds }
796 -----------------------------------------------------------------------------
797 -- Transformation Rules
799 rules :: { OrdList (LHsDecl RdrName) }
800 : rules ';' rule { $1 `snocOL` $3 }
803 | {- empty -} { nilOL }
805 rule :: { LHsDecl RdrName }
806 : STRING activation rule_forall infixexp '=' exp
807 { LL $ RuleD (HsRule (getSTRING $1)
808 ($2 `orElse` AlwaysActive)
809 $3 $4 placeHolderNames $6 placeHolderNames) }
811 activation :: { Maybe Activation }
812 : {- empty -} { Nothing }
813 | explicit_activation { Just $1 }
815 explicit_activation :: { Activation } -- In brackets
816 : '[' INTEGER ']' { ActiveAfter (fromInteger (getINTEGER $2)) }
817 | '[' '~' INTEGER ']' { ActiveBefore (fromInteger (getINTEGER $3)) }
819 rule_forall :: { [RuleBndr RdrName] }
820 : 'forall' rule_var_list '.' { $2 }
823 rule_var_list :: { [RuleBndr RdrName] }
825 | rule_var rule_var_list { $1 : $2 }
827 rule_var :: { RuleBndr RdrName }
828 : varid { RuleBndr $1 }
829 | '(' varid '::' ctype ')' { RuleBndrSig $2 $4 }
831 -----------------------------------------------------------------------------
832 -- Warnings and deprecations (c.f. rules)
834 warnings :: { OrdList (LHsDecl RdrName) }
835 : warnings ';' warning { $1 `appOL` $3 }
836 | warnings ';' { $1 }
838 | {- empty -} { nilOL }
840 -- SUP: TEMPORARY HACK, not checking for `module Foo'
841 warning :: { OrdList (LHsDecl RdrName) }
843 { toOL [ LL $ WarningD (Warning n (WarningTxt $ unLoc $2))
846 deprecations :: { OrdList (LHsDecl RdrName) }
847 : deprecations ';' deprecation { $1 `appOL` $3 }
848 | deprecations ';' { $1 }
850 | {- empty -} { nilOL }
852 -- SUP: TEMPORARY HACK, not checking for `module Foo'
853 deprecation :: { OrdList (LHsDecl RdrName) }
855 { toOL [ LL $ WarningD (Warning n (DeprecatedTxt $ unLoc $2))
858 strings :: { Located [FastString] }
859 : STRING { L1 [getSTRING $1] }
860 | '[' stringlist ']' { LL $ fromOL (unLoc $2) }
862 stringlist :: { Located (OrdList FastString) }
863 : stringlist ',' STRING { LL (unLoc $1 `snocOL` getSTRING $3) }
864 | STRING { LL (unitOL (getSTRING $1)) }
866 -----------------------------------------------------------------------------
868 annotation :: { LHsDecl RdrName }
869 : '{-# ANN' name_var aexp '#-}' { LL (AnnD $ HsAnnotation (ValueAnnProvenance (unLoc $2)) $3) }
870 | '{-# ANN' 'type' tycon aexp '#-}' { LL (AnnD $ HsAnnotation (TypeAnnProvenance (unLoc $3)) $4) }
871 | '{-# ANN' 'module' aexp '#-}' { LL (AnnD $ HsAnnotation ModuleAnnProvenance $3) }
874 -----------------------------------------------------------------------------
875 -- Foreign import and export declarations
877 fdecl :: { LHsDecl RdrName }
878 fdecl : 'import' callconv safety fspec
879 {% mkImport $2 $3 (unLoc $4) >>= return.LL }
880 | 'import' callconv fspec
881 {% do { d <- mkImport $2 (PlaySafe False) (unLoc $3);
883 | 'export' callconv fspec
884 {% mkExport $2 (unLoc $3) >>= return.LL }
886 callconv :: { CCallConv }
887 : 'stdcall' { StdCallConv }
888 | 'ccall' { CCallConv }
889 | 'prim' { PrimCallConv}
892 : 'unsafe' { PlayRisky }
893 | 'safe' { PlaySafe False }
894 | 'threadsafe' { PlaySafe True } -- deprecated alias
896 fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
897 : STRING var '::' sigtypedoc { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
898 | var '::' sigtypedoc { LL (noLoc nilFS, $1, $3) }
899 -- if the entity string is missing, it defaults to the empty string;
900 -- the meaning of an empty entity string depends on the calling
903 -----------------------------------------------------------------------------
906 opt_sig :: { Maybe (LHsType RdrName) }
907 : {- empty -} { Nothing }
908 | '::' sigtype { Just $2 }
910 opt_asig :: { Maybe (LHsType RdrName) }
911 : {- empty -} { Nothing }
912 | '::' atype { Just $2 }
914 sigtype :: { LHsType RdrName } -- Always a HsForAllTy,
915 -- to tell the renamer where to generalise
916 : ctype { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
917 -- Wrap an Implicit forall if there isn't one there already
919 sigtypedoc :: { LHsType RdrName } -- Always a HsForAllTy
920 : ctypedoc { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
921 -- Wrap an Implicit forall if there isn't one there already
923 sig_vars :: { Located [Located RdrName] }
924 : sig_vars ',' var { LL ($3 : unLoc $1) }
927 sigtypes1 :: { [LHsType RdrName] } -- Always HsForAllTys
929 | sigtype ',' sigtypes1 { $1 : $3 }
931 -----------------------------------------------------------------------------
934 infixtype :: { LHsType RdrName }
935 : btype qtyconop type { LL $ HsOpTy $1 $2 $3 }
936 | btype tyvarop type { LL $ HsOpTy $1 $2 $3 }
938 strict_mark :: { Located HsBang }
939 : '!' { L1 HsStrict }
940 | '{-# UNPACK' '#-}' '!' { LL HsUnbox }
942 -- A ctype is a for-all type
943 ctype :: { LHsType RdrName }
944 : 'forall' tv_bndrs '.' ctype { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
945 | context '=>' ctype { LL $ mkImplicitHsForAllTy $1 $3 }
946 -- A type of form (context => type) is an *implicit* HsForAllTy
947 | ipvar '::' type { LL (HsPredTy (HsIParam (unLoc $1) $3)) }
950 ----------------------
951 -- Notes for 'ctypedoc'
952 -- It would have been nice to simplify the grammar by unifying `ctype` and
953 -- ctypedoc` into one production, allowing comments on types everywhere (and
954 -- rejecting them after parsing, where necessary). This is however not possible
955 -- since it leads to ambiguity. The reason is the support for comments on record
957 -- data R = R { field :: Int -- ^ comment on the field }
958 -- If we allow comments on types here, it's not clear if the comment applies
959 -- to 'field' or to 'Int'. So we must use `ctype` to describe the type.
961 ctypedoc :: { LHsType RdrName }
962 : 'forall' tv_bndrs '.' ctypedoc { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
963 | context '=>' ctypedoc { LL $ mkImplicitHsForAllTy $1 $3 }
964 -- A type of form (context => type) is an *implicit* HsForAllTy
965 | ipvar '::' type { LL (HsPredTy (HsIParam (unLoc $1) $3)) }
968 ----------------------
969 -- Notes for 'context'
970 -- We parse a context as a btype so that we don't get reduce/reduce
971 -- errors in ctype. The basic problem is that
973 -- looks so much like a tuple type. We can't tell until we find the =>
975 -- We have the t1 ~ t2 form both in 'context' and in type,
976 -- to permit an individual equational constraint without parenthesis.
977 -- Thus for some reason we allow f :: a~b => blah
978 -- but not f :: ?x::Int => blah
979 context :: { LHsContext RdrName }
980 : btype '~' btype {% checkContext
981 (LL $ HsPredTy (HsEqualP $1 $3)) }
982 | btype {% checkContext $1 }
984 type :: { LHsType RdrName }
986 | btype qtyconop type { LL $ HsOpTy $1 $2 $3 }
987 | btype tyvarop type { LL $ HsOpTy $1 $2 $3 }
988 | btype '->' ctype { LL $ HsFunTy $1 $3 }
989 | btype '~' btype { LL $ HsPredTy (HsEqualP $1 $3) }
991 typedoc :: { LHsType RdrName }
993 | btype docprev { LL $ HsDocTy $1 $2 }
994 | btype qtyconop type { LL $ HsOpTy $1 $2 $3 }
995 | btype qtyconop type docprev { LL $ HsDocTy (L (comb3 $1 $2 $3) (HsOpTy $1 $2 $3)) $4 }
996 | btype tyvarop type { LL $ HsOpTy $1 $2 $3 }
997 | btype tyvarop type docprev { LL $ HsDocTy (L (comb3 $1 $2 $3) (HsOpTy $1 $2 $3)) $4 }
998 | btype '->' ctypedoc { LL $ HsFunTy $1 $3 }
999 | btype docprev '->' ctypedoc { LL $ HsFunTy (L (comb2 $1 $2) (HsDocTy $1 $2)) $4 }
1000 | btype '~' btype { LL $ HsPredTy (HsEqualP $1 $3) }
1002 btype :: { LHsType RdrName }
1003 : btype atype { LL $ HsAppTy $1 $2 }
1006 atype :: { LHsType RdrName }
1007 : gtycon { L1 (HsTyVar (unLoc $1)) }
1008 | tyvar { L1 (HsTyVar (unLoc $1)) }
1009 | strict_mark atype { LL (HsBangTy (unLoc $1) $2) } -- Constructor sigs only
1010 | '{' fielddecls '}' { LL $ HsRecTy $2 } -- Constructor sigs only
1011 | '(' ctype ',' comma_types1 ')' { LL $ HsTupleTy Boxed ($2:$4) }
1012 | '(#' comma_types1 '#)' { LL $ HsTupleTy Unboxed $2 }
1013 | '[' ctype ']' { LL $ HsListTy $2 }
1014 | '[:' ctype ':]' { LL $ HsPArrTy $2 }
1015 | '(' ctype ')' { LL $ HsParTy $2 }
1016 | '(' ctype '::' kind ')' { LL $ HsKindSig $2 (unLoc $4) }
1017 | '$(' exp ')' { LL $ HsSpliceTy (mkHsSplice $2 ) }
1018 | TH_ID_SPLICE { LL $ HsSpliceTy (mkHsSplice
1019 (L1 $ HsVar (mkUnqual varName
1020 (getTH_ID_SPLICE $1)))) } -- $x
1022 | INTEGER { L1 (HsNumTy (getINTEGER $1)) }
1024 -- An inst_type is what occurs in the head of an instance decl
1025 -- e.g. (Foo a, Gaz b) => Wibble a b
1026 -- It's kept as a single type, with a MonoDictTy at the right
1027 -- hand corner, for convenience.
1028 inst_type :: { LHsType RdrName }
1029 : sigtype {% checkInstType $1 }
1031 inst_types1 :: { [LHsType RdrName] }
1032 : inst_type { [$1] }
1033 | inst_type ',' inst_types1 { $1 : $3 }
1035 comma_types0 :: { [LHsType RdrName] }
1036 : comma_types1 { $1 }
1037 | {- empty -} { [] }
1039 comma_types1 :: { [LHsType RdrName] }
1041 | ctype ',' comma_types1 { $1 : $3 }
1043 tv_bndrs :: { [LHsTyVarBndr RdrName] }
1044 : tv_bndr tv_bndrs { $1 : $2 }
1045 | {- empty -} { [] }
1047 tv_bndr :: { LHsTyVarBndr RdrName }
1048 : tyvar { L1 (UserTyVar (unLoc $1)) }
1049 | '(' tyvar '::' kind ')' { LL (KindedTyVar (unLoc $2)
1052 fds :: { Located [Located (FunDep RdrName)] }
1053 : {- empty -} { noLoc [] }
1054 | '|' fds1 { LL (reverse (unLoc $2)) }
1056 fds1 :: { Located [Located (FunDep RdrName)] }
1057 : fds1 ',' fd { LL ($3 : unLoc $1) }
1060 fd :: { Located (FunDep RdrName) }
1061 : varids0 '->' varids0 { L (comb3 $1 $2 $3)
1062 (reverse (unLoc $1), reverse (unLoc $3)) }
1064 varids0 :: { Located [RdrName] }
1065 : {- empty -} { noLoc [] }
1066 | varids0 tyvar { LL (unLoc $2 : unLoc $1) }
1068 -----------------------------------------------------------------------------
1071 kind :: { Located Kind }
1073 | akind '->' kind { LL (mkArrowKind (unLoc $1) (unLoc $3)) }
1075 akind :: { Located Kind }
1076 : '*' { L1 liftedTypeKind }
1077 | '!' { L1 unliftedTypeKind }
1078 | '(' kind ')' { LL (unLoc $2) }
1081 -----------------------------------------------------------------------------
1082 -- Datatype declarations
1084 gadt_constrlist :: { Located [LConDecl RdrName] }
1085 : '{' gadt_constrs '}' { LL (unLoc $2) }
1086 | vocurly gadt_constrs close { $2 }
1088 gadt_constrs :: { Located [LConDecl RdrName] }
1089 : gadt_constrs ';' gadt_constr { sL (comb2 $1 (head $3)) ($3 ++ unLoc $1) }
1090 | gadt_constrs ';' { $1 }
1091 | gadt_constr { sL (getLoc (head $1)) $1 }
1093 -- We allow the following forms:
1094 -- C :: Eq a => a -> T a
1095 -- C :: forall a. Eq a => !a -> T a
1096 -- D { x,y :: a } :: T a
1097 -- forall a. Eq a => D { x,y :: a } :: T a
1099 gadt_constr :: { [LConDecl RdrName] }
1100 : con_list '::' sigtype
1101 { map (sL (comb2 $1 $3)) (mkGadtDecl (unLoc $1) $3) }
1103 -- Deprecated syntax for GADT record declarations
1104 | oqtycon '{' fielddecls '}' '::' sigtype
1105 {% do { cd <- mkDeprecatedGadtRecordDecl (comb2 $1 $6) $1 $3 $6
1108 constrs :: { Located [LConDecl RdrName] }
1109 : {- empty; a GHC extension -} { noLoc [] }
1110 | maybe_docnext '=' constrs1 { L (comb2 $2 $3) (addConDocs (unLoc $3) $1) }
1112 constrs1 :: { Located [LConDecl RdrName] }
1113 : constrs1 maybe_docnext '|' maybe_docprev constr { LL (addConDoc $5 $2 : addConDocFirst (unLoc $1) $4) }
1114 | constr { L1 [$1] }
1116 constr :: { LConDecl RdrName }
1117 : maybe_docnext forall context '=>' constr_stuff maybe_docprev
1118 { let (con,details) = unLoc $5 in
1119 addConDoc (L (comb4 $2 $3 $4 $5) (mkSimpleConDecl con (unLoc $2) $3 details))
1121 | maybe_docnext forall constr_stuff maybe_docprev
1122 { let (con,details) = unLoc $3 in
1123 addConDoc (L (comb2 $2 $3) (mkSimpleConDecl con (unLoc $2) (noLoc []) details))
1126 forall :: { Located [LHsTyVarBndr RdrName] }
1127 : 'forall' tv_bndrs '.' { LL $2 }
1128 | {- empty -} { noLoc [] }
1130 constr_stuff :: { Located (Located RdrName, HsConDeclDetails RdrName) }
1131 -- We parse the constructor declaration
1133 -- as a btype (treating C as a type constructor) and then convert C to be
1134 -- a data constructor. Reason: it might continue like this:
1136 -- in which case C really would be a type constructor. We can't resolve this
1137 -- ambiguity till we come across the constructor oprerator :% (or not, more usually)
1138 : btype {% splitCon $1 >>= return.LL }
1139 | btype conop btype { LL ($2, InfixCon $1 $3) }
1141 fielddecls :: { [ConDeclField RdrName] }
1142 : {- empty -} { [] }
1143 | fielddecls1 { $1 }
1145 fielddecls1 :: { [ConDeclField RdrName] }
1146 : fielddecl maybe_docnext ',' maybe_docprev fielddecls1
1147 { [ addFieldDoc f $4 | f <- $1 ] ++ addFieldDocs $5 $2 }
1148 -- This adds the doc $4 to each field separately
1151 fielddecl :: { [ConDeclField RdrName] } -- A list because of f,g :: Int
1152 : maybe_docnext sig_vars '::' ctype maybe_docprev { [ ConDeclField fld $4 ($1 `mplus` $5)
1153 | fld <- reverse (unLoc $2) ] }
1155 -- We allow the odd-looking 'inst_type' in a deriving clause, so that
1156 -- we can do deriving( forall a. C [a] ) in a newtype (GHC extension).
1157 -- The 'C [a]' part is converted to an HsPredTy by checkInstType
1158 -- We don't allow a context, but that's sorted out by the type checker.
1159 deriving :: { Located (Maybe [LHsType RdrName]) }
1160 : {- empty -} { noLoc Nothing }
1161 | 'deriving' qtycon {% do { let { L loc tv = $2 }
1162 ; p <- checkInstType (L loc (HsTyVar tv))
1163 ; return (LL (Just [p])) } }
1164 | 'deriving' '(' ')' { LL (Just []) }
1165 | 'deriving' '(' inst_types1 ')' { LL (Just $3) }
1166 -- Glasgow extension: allow partial
1167 -- applications in derivings
1169 -----------------------------------------------------------------------------
1170 -- Value definitions
1172 {- There's an awkward overlap with a type signature. Consider
1173 f :: Int -> Int = ...rhs...
1174 Then we can't tell whether it's a type signature or a value
1175 definition with a result signature until we see the '='.
1176 So we have to inline enough to postpone reductions until we know.
1180 ATTENTION: Dirty Hackery Ahead! If the second alternative of vars is var
1181 instead of qvar, we get another shift/reduce-conflict. Consider the
1184 { (^^) :: Int->Int ; } Type signature; only var allowed
1186 { (^^) :: Int->Int = ... ; } Value defn with result signature;
1187 qvar allowed (because of instance decls)
1189 We can't tell whether to reduce var to qvar until after we've read the signatures.
1192 docdecl :: { LHsDecl RdrName }
1193 : docdecld { L1 (DocD (unLoc $1)) }
1195 docdecld :: { LDocDecl RdrName }
1196 : docnext { L1 (DocCommentNext (unLoc $1)) }
1197 | docprev { L1 (DocCommentPrev (unLoc $1)) }
1198 | docnamed { L1 (case (unLoc $1) of (n, doc) -> DocCommentNamed n doc) }
1199 | docsection { L1 (case (unLoc $1) of (n, doc) -> DocGroup n doc) }
1201 decl :: { Located (OrdList (LHsDecl RdrName)) }
1203 | '!' aexp rhs {% do { pat <- checkPattern $2;
1204 return (LL $ unitOL $ LL $ ValD (
1205 PatBind (LL $ BangPat pat) (unLoc $3)
1206 placeHolderType placeHolderNames)) } }
1207 | infixexp opt_sig rhs {% do { r <- checkValDef $1 $2 $3;
1208 let { l = comb2 $1 $> };
1209 return $! (sL l (unitOL $! (sL l $ ValD r))) } }
1210 | docdecl { LL $ unitOL $1 }
1212 rhs :: { Located (GRHSs RdrName) }
1213 : '=' exp wherebinds { sL (comb3 $1 $2 $3) $ GRHSs (unguardedRHS $2) (unLoc $3) }
1214 | gdrhs wherebinds { LL $ GRHSs (reverse (unLoc $1)) (unLoc $2) }
1216 gdrhs :: { Located [LGRHS RdrName] }
1217 : gdrhs gdrh { LL ($2 : unLoc $1) }
1220 gdrh :: { LGRHS RdrName }
1221 : '|' guardquals '=' exp { sL (comb2 $1 $>) $ GRHS (unLoc $2) $4 }
1223 sigdecl :: { Located (OrdList (LHsDecl RdrName)) }
1224 : infixexp '::' sigtypedoc
1225 {% do s <- checkValSig $1 $3;
1226 return (LL $ unitOL (LL $ SigD s)) }
1227 -- See the above notes for why we need infixexp here
1228 | var ',' sig_vars '::' sigtypedoc
1229 { LL $ toOL [ LL $ SigD (TypeSig n $5) | n <- $1 : unLoc $3 ] }
1230 | infix prec ops { LL $ toOL [ LL $ SigD (FixSig (FixitySig n (Fixity $2 (unLoc $1))))
1232 | '{-# INLINE' activation qvar '#-}'
1233 { LL $ unitOL (LL $ SigD (InlineSig $3 (mkInlineSpec $2 FunLike (getINLINE $1)))) }
1234 | '{-# INLINE_CONLIKE' activation qvar '#-}'
1235 { LL $ unitOL (LL $ SigD (InlineSig $3 (mkInlineSpec $2 ConLike (getINLINE_CONLIKE $1)))) }
1236 | '{-# SPECIALISE' qvar '::' sigtypes1 '#-}'
1237 { LL $ toOL [ LL $ SigD (SpecSig $2 t defaultInlineSpec)
1239 | '{-# SPECIALISE_INLINE' activation qvar '::' sigtypes1 '#-}'
1240 { LL $ toOL [ LL $ SigD (SpecSig $3 t (mkInlineSpec $2 FunLike (getSPEC_INLINE $1)))
1242 | '{-# SPECIALISE' 'instance' inst_type '#-}'
1243 { LL $ unitOL (LL $ SigD (SpecInstSig $3)) }
1245 -----------------------------------------------------------------------------
1248 exp :: { LHsExpr RdrName }
1249 : infixexp '::' sigtype { LL $ ExprWithTySig $1 $3 }
1250 | infixexp '-<' exp { LL $ HsArrApp $1 $3 placeHolderType HsFirstOrderApp True }
1251 | infixexp '>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsFirstOrderApp False }
1252 | infixexp '-<<' exp { LL $ HsArrApp $1 $3 placeHolderType HsHigherOrderApp True }
1253 | infixexp '>>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsHigherOrderApp False}
1256 infixexp :: { LHsExpr RdrName }
1258 | infixexp qop exp10 { LL (OpApp $1 $2 (panic "fixity") $3) }
1260 exp10 :: { LHsExpr RdrName }
1261 : '\\' apat apats opt_asig '->' exp
1262 { LL $ HsLam (mkMatchGroup [LL $ Match ($2:$3) $4
1265 | 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
1266 | 'if' exp 'then' exp 'else' exp { LL $ HsIf $2 $4 $6 }
1267 | 'case' exp 'of' altslist { LL $ HsCase $2 (mkMatchGroup (unLoc $4)) }
1268 | '-' fexp { LL $ NegApp $2 noSyntaxExpr }
1270 | 'do' stmtlist {% let loc = comb2 $1 $2 in
1271 checkDo loc (unLoc $2) >>= \ (stmts,body) ->
1272 return (L loc (mkHsDo DoExpr stmts body)) }
1273 | 'mdo' stmtlist {% let loc = comb2 $1 $2 in
1274 checkDo loc (unLoc $2) >>= \ (stmts,body) ->
1275 return (L loc (mkHsDo (MDoExpr noPostTcTable) stmts body)) }
1276 | scc_annot exp { LL $ if opt_SccProfilingOn
1277 then HsSCC (unLoc $1) $2
1279 | hpc_annot exp { LL $ if opt_Hpc
1280 then HsTickPragma (unLoc $1) $2
1283 | 'proc' aexp '->' exp
1284 {% checkPattern $2 >>= \ p ->
1285 return (LL $ HsProc p (LL $ HsCmdTop $4 []
1286 placeHolderType undefined)) }
1287 -- TODO: is LL right here?
1289 | '{-# CORE' STRING '#-}' exp { LL $ HsCoreAnn (getSTRING $2) $4 }
1290 -- hdaume: core annotation
1293 scc_annot :: { Located FastString }
1294 : '_scc_' STRING {% (addWarning Opt_WarnWarningsDeprecations (getLoc $1) (text "_scc_ is deprecated; use an SCC pragma instead")) >>= \_ ->
1295 ( do scc <- getSCC $2; return $ LL scc ) }
1296 | '{-# SCC' STRING '#-}' {% do scc <- getSCC $2; return $ LL scc }
1298 hpc_annot :: { Located (FastString,(Int,Int),(Int,Int)) }
1299 : '{-# GENERATED' STRING INTEGER ':' INTEGER '-' INTEGER ':' INTEGER '#-}'
1300 { LL $ (getSTRING $2
1301 ,( fromInteger $ getINTEGER $3
1302 , fromInteger $ getINTEGER $5
1304 ,( fromInteger $ getINTEGER $7
1305 , fromInteger $ getINTEGER $9
1310 fexp :: { LHsExpr RdrName }
1311 : fexp aexp { LL $ HsApp $1 $2 }
1314 aexp :: { LHsExpr RdrName }
1315 : qvar '@' aexp { LL $ EAsPat $1 $3 }
1316 | '~' aexp { LL $ ELazyPat $2 }
1319 aexp1 :: { LHsExpr RdrName }
1320 : aexp1 '{' fbinds '}' {% do { r <- mkRecConstrOrUpdate $1 (comb2 $2 $4) $3
1324 -- Here was the syntax for type applications that I was planning
1325 -- but there are difficulties (e.g. what order for type args)
1326 -- so it's not enabled yet.
1327 -- But this case *is* used for the left hand side of a generic definition,
1328 -- which is parsed as an expression before being munged into a pattern
1329 | qcname '{|' type '|}' { LL $ HsApp (sL (getLoc $1) (HsVar (unLoc $1)))
1330 (sL (getLoc $3) (HsType $3)) }
1332 aexp2 :: { LHsExpr RdrName }
1333 : ipvar { L1 (HsIPVar $! unLoc $1) }
1334 | qcname { L1 (HsVar $! unLoc $1) }
1335 | literal { L1 (HsLit $! unLoc $1) }
1336 -- This will enable overloaded strings permanently. Normally the renamer turns HsString
1337 -- into HsOverLit when -foverloaded-strings is on.
1338 -- | STRING { sL (getLoc $1) (HsOverLit $! mkHsIsString (getSTRING $1) placeHolderType) }
1339 | INTEGER { sL (getLoc $1) (HsOverLit $! mkHsIntegral (getINTEGER $1) placeHolderType) }
1340 | RATIONAL { sL (getLoc $1) (HsOverLit $! mkHsFractional (getRATIONAL $1) placeHolderType) }
1342 -- N.B.: sections get parsed by these next two productions.
1343 -- This allows you to write, e.g., '(+ 3, 4 -)', which isn't correct Haskell98
1344 -- (you'd have to write '((+ 3), (4 -))')
1345 -- but the less cluttered version fell out of having texps.
1346 | '(' texp ')' { LL (HsPar $2) }
1347 | '(' tup_exprs ')' { LL (ExplicitTuple $2 Boxed) }
1349 | '(#' texp '#)' { LL (ExplicitTuple [Present $2] Unboxed) }
1350 | '(#' tup_exprs '#)' { LL (ExplicitTuple $2 Unboxed) }
1352 | '[' list ']' { LL (unLoc $2) }
1353 | '[:' parr ':]' { LL (unLoc $2) }
1354 | '_' { L1 EWildPat }
1356 -- Template Haskell Extension
1357 | TH_ID_SPLICE { L1 $ HsSpliceE (mkHsSplice
1358 (L1 $ HsVar (mkUnqual varName
1359 (getTH_ID_SPLICE $1)))) } -- $x
1360 | '$(' exp ')' { LL $ HsSpliceE (mkHsSplice $2) } -- $( exp )
1362 | TH_QUASIQUOTE { let { loc = getLoc $1
1363 ; ITquasiQuote (quoter, quote, quoteSpan) = unLoc $1
1364 ; quoterId = mkUnqual varName quoter
1366 in sL loc $ HsQuasiQuoteE (mkHsQuasiQuote quoterId quoteSpan quote) }
1367 | TH_VAR_QUOTE qvar { LL $ HsBracket (VarBr (unLoc $2)) }
1368 | TH_VAR_QUOTE qcon { LL $ HsBracket (VarBr (unLoc $2)) }
1369 | TH_TY_QUOTE tyvar { LL $ HsBracket (VarBr (unLoc $2)) }
1370 | TH_TY_QUOTE gtycon { LL $ HsBracket (VarBr (unLoc $2)) }
1371 | '[|' exp '|]' { LL $ HsBracket (ExpBr $2) }
1372 | '[t|' ctype '|]' { LL $ HsBracket (TypBr $2) }
1373 | '[p|' infixexp '|]' {% checkPattern $2 >>= \p ->
1374 return (LL $ HsBracket (PatBr p)) }
1375 | '[d|' cvtopbody '|]' {% checkDecBrGroup $2 >>= \g ->
1376 return (LL $ HsBracket (DecBr g)) }
1378 -- arrow notation extension
1379 | '(|' aexp2 cmdargs '|)' { LL $ HsArrForm $2 Nothing (reverse $3) }
1381 cmdargs :: { [LHsCmdTop RdrName] }
1382 : cmdargs acmd { $2 : $1 }
1383 | {- empty -} { [] }
1385 acmd :: { LHsCmdTop RdrName }
1386 : aexp2 { L1 $ HsCmdTop $1 [] placeHolderType undefined }
1388 cvtopbody :: { [LHsDecl RdrName] }
1389 : '{' cvtopdecls0 '}' { $2 }
1390 | vocurly cvtopdecls0 close { $2 }
1392 cvtopdecls0 :: { [LHsDecl RdrName] }
1393 : {- empty -} { [] }
1396 -----------------------------------------------------------------------------
1397 -- Tuple expressions
1399 -- "texp" is short for tuple expressions:
1400 -- things that can appear unparenthesized as long as they're
1401 -- inside parens or delimitted by commas
1402 texp :: { LHsExpr RdrName }
1405 -- Note [Parsing sections]
1406 -- ~~~~~~~~~~~~~~~~~~~~~~~
1407 -- We include left and right sections here, which isn't
1408 -- technically right according to Haskell 98. For example
1409 -- (3 +, True) isn't legal
1410 -- However, we want to parse bang patterns like
1412 -- and it's convenient to do so here as a section
1413 -- Then when converting expr to pattern we unravel it again
1414 -- Meanwhile, the renamer checks that real sections appear
1416 | infixexp qop { LL $ SectionL $1 $2 }
1417 | qopm infixexp { LL $ SectionR $1 $2 }
1419 -- View patterns get parenthesized above
1420 | exp '->' exp { LL $ EViewPat $1 $3 }
1422 -- Always at least one comma
1423 tup_exprs :: { [HsTupArg RdrName] }
1424 : texp commas_tup_tail { Present $1 : $2 }
1425 | commas tup_tail { replicate $1 missingTupArg ++ $2 }
1427 -- Always starts with commas; always follows an expr
1428 commas_tup_tail :: { [HsTupArg RdrName] }
1429 commas_tup_tail : commas tup_tail { replicate ($1-1) missingTupArg ++ $2 }
1431 -- Always follows a comma
1432 tup_tail :: { [HsTupArg RdrName] }
1433 : texp commas_tup_tail { Present $1 : $2 }
1434 | texp { [Present $1] }
1435 | {- empty -} { [missingTupArg] }
1437 -----------------------------------------------------------------------------
1440 -- The rules below are little bit contorted to keep lexps left-recursive while
1441 -- avoiding another shift/reduce-conflict.
1443 list :: { LHsExpr RdrName }
1444 : texp { L1 $ ExplicitList placeHolderType [$1] }
1445 | lexps { L1 $ ExplicitList placeHolderType (reverse (unLoc $1)) }
1446 | texp '..' { LL $ ArithSeq noPostTcExpr (From $1) }
1447 | texp ',' exp '..' { LL $ ArithSeq noPostTcExpr (FromThen $1 $3) }
1448 | texp '..' exp { LL $ ArithSeq noPostTcExpr (FromTo $1 $3) }
1449 | texp ',' exp '..' exp { LL $ ArithSeq noPostTcExpr (FromThenTo $1 $3 $5) }
1450 | texp '|' flattenedpquals { sL (comb2 $1 $>) $ mkHsDo ListComp (unLoc $3) $1 }
1452 lexps :: { Located [LHsExpr RdrName] }
1453 : lexps ',' texp { LL (((:) $! $3) $! unLoc $1) }
1454 | texp ',' texp { LL [$3,$1] }
1456 -----------------------------------------------------------------------------
1457 -- List Comprehensions
1459 flattenedpquals :: { Located [LStmt RdrName] }
1460 : pquals { case (unLoc $1) of
1461 ParStmt [(qs, _)] -> L1 qs
1462 -- We just had one thing in our "parallel" list so
1463 -- we simply return that thing directly
1466 -- We actually found some actual parallel lists so
1467 -- we leave them into as a ParStmt
1470 pquals :: { LStmt RdrName }
1471 : pquals1 { L1 (ParStmt [(qs, undefined) | qs <- (reverse (unLoc $1))]) }
1473 pquals1 :: { Located [[LStmt RdrName]] }
1474 : pquals1 '|' squals { LL (unLoc $3 : unLoc $1) }
1475 | squals { L (getLoc $1) [unLoc $1] }
1477 squals :: { Located [LStmt RdrName] }
1478 : squals1 { L (getLoc $1) (reverse (unLoc $1)) }
1480 squals1 :: { Located [LStmt RdrName] }
1481 : transformquals1 { LL (unLoc $1) }
1483 transformquals1 :: { Located [LStmt RdrName] }
1484 : transformquals1 ',' transformqual { LL $ [LL ((unLoc $3) (unLoc $1))] }
1485 | transformquals1 ',' qual { LL ($3 : unLoc $1) }
1486 -- | transformquals1 ',' '{|' pquals '|}' { LL ($4 : unLoc $1) }
1487 | transformqual { LL $ [LL ((unLoc $1) [])] }
1489 -- | '{|' pquals '|}' { L1 [$2] }
1492 -- It is possible to enable bracketing (associating) qualifier lists by uncommenting the lines with {| |}
1493 -- above. Due to a lack of consensus on the syntax, this feature is not being used until we get user
1494 -- demand. Note that the {| |} symbols are reused from -XGenerics and hence if you want to compile
1495 -- a program that makes use of this temporary syntax you must supply that flag to GHC
1497 transformqual :: { Located ([LStmt RdrName] -> Stmt RdrName) }
1498 : 'then' exp { LL $ \leftStmts -> (mkTransformStmt (reverse leftStmts) $2) }
1500 | 'then' exp 'by' exp { LL $ \leftStmts -> (mkTransformByStmt (reverse leftStmts) $2 $4) }
1501 | 'then' 'group' 'by' exp { LL $ \leftStmts -> (mkGroupByStmt (reverse leftStmts) $4) }
1503 -- These two productions deliberately have a shift-reduce conflict. I have made 'group' into a special_id,
1504 -- which means you can enable TransformListComp while still using Data.List.group. However, this makes the two
1505 -- productions ambiguous. I've set things up so that Happy chooses to resolve the conflict in that case by
1506 -- choosing the "group by" variant, which is what we want.
1508 -- This is rather dubious: the user might be confused as to how to parse this statement. However, it is a good
1509 -- practical choice. NB: Data.List.group :: [a] -> [[a]], so using the first production would not even type check
1510 -- if /that/ is the group function we conflict with.
1511 | 'then' 'group' 'using' exp { LL $ \leftStmts -> (mkGroupUsingStmt (reverse leftStmts) $4) }
1512 | 'then' 'group' 'by' exp 'using' exp { LL $ \leftStmts -> (mkGroupByUsingStmt (reverse leftStmts) $4 $6) }
1514 -----------------------------------------------------------------------------
1515 -- Parallel array expressions
1517 -- The rules below are little bit contorted; see the list case for details.
1518 -- Note that, in contrast to lists, we only have finite arithmetic sequences.
1519 -- Moreover, we allow explicit arrays with no element (represented by the nil
1520 -- constructor in the list case).
1522 parr :: { LHsExpr RdrName }
1523 : { noLoc (ExplicitPArr placeHolderType []) }
1524 | texp { L1 $ ExplicitPArr placeHolderType [$1] }
1525 | lexps { L1 $ ExplicitPArr placeHolderType
1526 (reverse (unLoc $1)) }
1527 | texp '..' exp { LL $ PArrSeq noPostTcExpr (FromTo $1 $3) }
1528 | texp ',' exp '..' exp { LL $ PArrSeq noPostTcExpr (FromThenTo $1 $3 $5) }
1529 | texp '|' flattenedpquals { LL $ mkHsDo PArrComp (unLoc $3) $1 }
1531 -- We are reusing `lexps' and `flattenedpquals' from the list case.
1533 -----------------------------------------------------------------------------
1536 guardquals :: { Located [LStmt RdrName] }
1537 : guardquals1 { L (getLoc $1) (reverse (unLoc $1)) }
1539 guardquals1 :: { Located [LStmt RdrName] }
1540 : guardquals1 ',' qual { LL ($3 : unLoc $1) }
1543 -----------------------------------------------------------------------------
1544 -- Case alternatives
1546 altslist :: { Located [LMatch RdrName] }
1547 : '{' alts '}' { LL (reverse (unLoc $2)) }
1548 | vocurly alts close { L (getLoc $2) (reverse (unLoc $2)) }
1550 alts :: { Located [LMatch RdrName] }
1551 : alts1 { L1 (unLoc $1) }
1552 | ';' alts { LL (unLoc $2) }
1554 alts1 :: { Located [LMatch RdrName] }
1555 : alts1 ';' alt { LL ($3 : unLoc $1) }
1556 | alts1 ';' { LL (unLoc $1) }
1559 alt :: { LMatch RdrName }
1560 : pat opt_sig alt_rhs { LL (Match [$1] $2 (unLoc $3)) }
1562 alt_rhs :: { Located (GRHSs RdrName) }
1563 : ralt wherebinds { LL (GRHSs (unLoc $1) (unLoc $2)) }
1565 ralt :: { Located [LGRHS RdrName] }
1566 : '->' exp { LL (unguardedRHS $2) }
1567 | gdpats { L1 (reverse (unLoc $1)) }
1569 gdpats :: { Located [LGRHS RdrName] }
1570 : gdpats gdpat { LL ($2 : unLoc $1) }
1573 gdpat :: { LGRHS RdrName }
1574 : '|' guardquals '->' exp { sL (comb2 $1 $>) $ GRHS (unLoc $2) $4 }
1576 -- 'pat' recognises a pattern, including one with a bang at the top
1577 -- e.g. "!x" or "!(x,y)" or "C a b" etc
1578 -- Bangs inside are parsed as infix operator applications, so that
1579 -- we parse them right when bang-patterns are off
1580 pat :: { LPat RdrName }
1581 pat : exp {% checkPattern $1 }
1582 | '!' aexp {% checkPattern (LL (SectionR (L1 (HsVar bang_RDR)) $2)) }
1584 apat :: { LPat RdrName }
1585 apat : aexp {% checkPattern $1 }
1586 | '!' aexp {% checkPattern (LL (SectionR (L1 (HsVar bang_RDR)) $2)) }
1588 apats :: { [LPat RdrName] }
1589 : apat apats { $1 : $2 }
1590 | {- empty -} { [] }
1592 -----------------------------------------------------------------------------
1593 -- Statement sequences
1595 stmtlist :: { Located [LStmt RdrName] }
1596 : '{' stmts '}' { LL (unLoc $2) }
1597 | vocurly stmts close { $2 }
1599 -- do { ;; s ; s ; ; s ;; }
1600 -- The last Stmt should be an expression, but that's hard to enforce
1601 -- here, because we need too much lookahead if we see do { e ; }
1602 -- So we use ExprStmts throughout, and switch the last one over
1603 -- in ParseUtils.checkDo instead
1604 stmts :: { Located [LStmt RdrName] }
1605 : stmt stmts_help { LL ($1 : unLoc $2) }
1606 | ';' stmts { LL (unLoc $2) }
1607 | {- empty -} { noLoc [] }
1609 stmts_help :: { Located [LStmt RdrName] } -- might be empty
1610 : ';' stmts { LL (unLoc $2) }
1611 | {- empty -} { noLoc [] }
1613 -- For typing stmts at the GHCi prompt, where
1614 -- the input may consist of just comments.
1615 maybe_stmt :: { Maybe (LStmt RdrName) }
1617 | {- nothing -} { Nothing }
1619 stmt :: { LStmt RdrName }
1621 | 'rec' stmtlist { LL $ mkRecStmt (unLoc $2) }
1623 qual :: { LStmt RdrName }
1624 : pat '<-' exp { LL $ mkBindStmt $1 $3 }
1625 | exp { L1 $ mkExprStmt $1 }
1626 | 'let' binds { LL $ LetStmt (unLoc $2) }
1628 -----------------------------------------------------------------------------
1629 -- Record Field Update/Construction
1631 fbinds :: { ([HsRecField RdrName (LHsExpr RdrName)], Bool) }
1633 | {- empty -} { ([], False) }
1635 fbinds1 :: { ([HsRecField RdrName (LHsExpr RdrName)], Bool) }
1636 : fbind ',' fbinds1 { case $3 of (flds, dd) -> ($1 : flds, dd) }
1637 | fbind { ([$1], False) }
1638 | '..' { ([], True) }
1640 fbind :: { HsRecField RdrName (LHsExpr RdrName) }
1641 : qvar '=' exp { HsRecField $1 $3 False }
1642 | qvar { HsRecField $1 (L (getLoc $1) (HsVar (unLoc $1))) True }
1643 -- Here's where we say that plain 'x'
1644 -- means exactly 'x = x'. The pun-flag boolean is
1645 -- there so we can still print it right
1647 -----------------------------------------------------------------------------
1648 -- Implicit Parameter Bindings
1650 dbinds :: { Located [LIPBind RdrName] }
1651 : dbinds ';' dbind { let { this = $3; rest = unLoc $1 }
1652 in rest `seq` this `seq` LL (this : rest) }
1653 | dbinds ';' { LL (unLoc $1) }
1654 | dbind { let this = $1 in this `seq` L1 [this] }
1655 -- | {- empty -} { [] }
1657 dbind :: { LIPBind RdrName }
1658 dbind : ipvar '=' exp { LL (IPBind (unLoc $1) $3) }
1660 ipvar :: { Located (IPName RdrName) }
1661 : IPDUPVARID { L1 (IPName (mkUnqual varName (getIPDUPVARID $1))) }
1663 -----------------------------------------------------------------------------
1664 -- Warnings and deprecations
1666 namelist :: { Located [RdrName] }
1667 namelist : name_var { L1 [unLoc $1] }
1668 | name_var ',' namelist { LL (unLoc $1 : unLoc $3) }
1670 name_var :: { Located RdrName }
1671 name_var : var { $1 }
1674 -----------------------------------------
1675 -- Data constructors
1676 qcon :: { Located RdrName }
1678 | '(' qconsym ')' { LL (unLoc $2) }
1679 | sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1680 -- The case of '[:' ':]' is part of the production `parr'
1682 con :: { Located RdrName }
1684 | '(' consym ')' { LL (unLoc $2) }
1685 | sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1687 con_list :: { Located [Located RdrName] }
1688 con_list : con { L1 [$1] }
1689 | con ',' con_list { LL ($1 : unLoc $3) }
1691 sysdcon :: { Located DataCon } -- Wired in data constructors
1692 : '(' ')' { LL unitDataCon }
1693 | '(' commas ')' { LL $ tupleCon Boxed ($2 + 1) }
1694 | '(#' '#)' { LL $ unboxedSingletonDataCon }
1695 | '(#' commas '#)' { LL $ tupleCon Unboxed ($2 + 1) }
1696 | '[' ']' { LL nilDataCon }
1698 conop :: { Located RdrName }
1700 | '`' conid '`' { LL (unLoc $2) }
1702 qconop :: { Located RdrName }
1704 | '`' qconid '`' { LL (unLoc $2) }
1706 -----------------------------------------------------------------------------
1707 -- Type constructors
1709 gtycon :: { Located RdrName } -- A "general" qualified tycon
1711 | '(' ')' { LL $ getRdrName unitTyCon }
1712 | '(' commas ')' { LL $ getRdrName (tupleTyCon Boxed ($2 + 1)) }
1713 | '(#' '#)' { LL $ getRdrName unboxedSingletonTyCon }
1714 | '(#' commas '#)' { LL $ getRdrName (tupleTyCon Unboxed ($2 + 1)) }
1715 | '(' '->' ')' { LL $ getRdrName funTyCon }
1716 | '[' ']' { LL $ listTyCon_RDR }
1717 | '[:' ':]' { LL $ parrTyCon_RDR }
1719 oqtycon :: { Located RdrName } -- An "ordinary" qualified tycon
1721 | '(' qtyconsym ')' { LL (unLoc $2) }
1723 qtyconop :: { Located RdrName } -- Qualified or unqualified
1725 | '`' qtycon '`' { LL (unLoc $2) }
1727 qtycon :: { Located RdrName } -- Qualified or unqualified
1728 : QCONID { L1 $! mkQual tcClsName (getQCONID $1) }
1729 | PREFIXQCONSYM { L1 $! mkQual tcClsName (getPREFIXQCONSYM $1) }
1732 tycon :: { Located RdrName } -- Unqualified
1733 : CONID { L1 $! mkUnqual tcClsName (getCONID $1) }
1735 qtyconsym :: { Located RdrName }
1736 : QCONSYM { L1 $! mkQual tcClsName (getQCONSYM $1) }
1739 tyconsym :: { Located RdrName }
1740 : CONSYM { L1 $! mkUnqual tcClsName (getCONSYM $1) }
1742 -----------------------------------------------------------------------------
1745 op :: { Located RdrName } -- used in infix decls
1749 varop :: { Located RdrName }
1751 | '`' varid '`' { LL (unLoc $2) }
1753 qop :: { LHsExpr RdrName } -- used in sections
1754 : qvarop { L1 $ HsVar (unLoc $1) }
1755 | qconop { L1 $ HsVar (unLoc $1) }
1757 qopm :: { LHsExpr RdrName } -- used in sections
1758 : qvaropm { L1 $ HsVar (unLoc $1) }
1759 | qconop { L1 $ HsVar (unLoc $1) }
1761 qvarop :: { Located RdrName }
1763 | '`' qvarid '`' { LL (unLoc $2) }
1765 qvaropm :: { Located RdrName }
1766 : qvarsym_no_minus { $1 }
1767 | '`' qvarid '`' { LL (unLoc $2) }
1769 -----------------------------------------------------------------------------
1772 tyvar :: { Located RdrName }
1773 tyvar : tyvarid { $1 }
1774 | '(' tyvarsym ')' { LL (unLoc $2) }
1776 tyvarop :: { Located RdrName }
1777 tyvarop : '`' tyvarid '`' { LL (unLoc $2) }
1779 | '.' {% parseErrorSDoc (getLoc $1)
1780 (vcat [ptext (sLit "Illegal symbol '.' in type"),
1781 ptext (sLit "Perhaps you intended -XRankNTypes or similar flag"),
1782 ptext (sLit "to enable explicit-forall syntax: forall <tvs>. <type>")])
1785 tyvarid :: { Located RdrName }
1786 : VARID { L1 $! mkUnqual tvName (getVARID $1) }
1787 | special_id { L1 $! mkUnqual tvName (unLoc $1) }
1788 | 'unsafe' { L1 $! mkUnqual tvName (fsLit "unsafe") }
1789 | 'safe' { L1 $! mkUnqual tvName (fsLit "safe") }
1790 | 'threadsafe' { L1 $! mkUnqual tvName (fsLit "threadsafe") }
1792 tyvarsym :: { Located RdrName }
1793 -- Does not include "!", because that is used for strictness marks
1794 -- or ".", because that separates the quantified type vars from the rest
1795 -- or "*", because that's used for kinds
1796 tyvarsym : VARSYM { L1 $! mkUnqual tvName (getVARSYM $1) }
1798 -----------------------------------------------------------------------------
1801 var :: { Located RdrName }
1803 | '(' varsym ')' { LL (unLoc $2) }
1805 qvar :: { Located RdrName }
1807 | '(' varsym ')' { LL (unLoc $2) }
1808 | '(' qvarsym1 ')' { LL (unLoc $2) }
1809 -- We've inlined qvarsym here so that the decision about
1810 -- whether it's a qvar or a var can be postponed until
1811 -- *after* we see the close paren.
1813 qvarid :: { Located RdrName }
1815 | QVARID { L1 $! mkQual varName (getQVARID $1) }
1816 | PREFIXQVARSYM { L1 $! mkQual varName (getPREFIXQVARSYM $1) }
1818 varid :: { Located RdrName }
1819 : VARID { L1 $! mkUnqual varName (getVARID $1) }
1820 | special_id { L1 $! mkUnqual varName (unLoc $1) }
1821 | 'unsafe' { L1 $! mkUnqual varName (fsLit "unsafe") }
1822 | 'safe' { L1 $! mkUnqual varName (fsLit "safe") }
1823 | 'threadsafe' { L1 $! mkUnqual varName (fsLit "threadsafe") }
1824 | 'forall' { L1 $! mkUnqual varName (fsLit "forall") }
1825 | 'family' { L1 $! mkUnqual varName (fsLit "family") }
1827 qvarsym :: { Located RdrName }
1831 qvarsym_no_minus :: { Located RdrName }
1832 : varsym_no_minus { $1 }
1835 qvarsym1 :: { Located RdrName }
1836 qvarsym1 : QVARSYM { L1 $ mkQual varName (getQVARSYM $1) }
1838 varsym :: { Located RdrName }
1839 : varsym_no_minus { $1 }
1840 | '-' { L1 $ mkUnqual varName (fsLit "-") }
1842 varsym_no_minus :: { Located RdrName } -- varsym not including '-'
1843 : VARSYM { L1 $ mkUnqual varName (getVARSYM $1) }
1844 | special_sym { L1 $ mkUnqual varName (unLoc $1) }
1847 -- These special_ids are treated as keywords in various places,
1848 -- but as ordinary ids elsewhere. 'special_id' collects all these
1849 -- except 'unsafe', 'forall', and 'family' whose treatment differs
1850 -- depending on context
1851 special_id :: { Located FastString }
1853 : 'as' { L1 (fsLit "as") }
1854 | 'qualified' { L1 (fsLit "qualified") }
1855 | 'hiding' { L1 (fsLit "hiding") }
1856 | 'export' { L1 (fsLit "export") }
1857 | 'label' { L1 (fsLit "label") }
1858 | 'dynamic' { L1 (fsLit "dynamic") }
1859 | 'stdcall' { L1 (fsLit "stdcall") }
1860 | 'ccall' { L1 (fsLit "ccall") }
1861 | 'prim' { L1 (fsLit "prim") }
1862 | 'group' { L1 (fsLit "group") }
1864 special_sym :: { Located FastString }
1865 special_sym : '!' { L1 (fsLit "!") }
1866 | '.' { L1 (fsLit ".") }
1867 | '*' { L1 (fsLit "*") }
1869 -----------------------------------------------------------------------------
1870 -- Data constructors
1872 qconid :: { Located RdrName } -- Qualified or unqualified
1874 | QCONID { L1 $! mkQual dataName (getQCONID $1) }
1875 | PREFIXQCONSYM { L1 $! mkQual dataName (getPREFIXQCONSYM $1) }
1877 conid :: { Located RdrName }
1878 : CONID { L1 $ mkUnqual dataName (getCONID $1) }
1880 qconsym :: { Located RdrName } -- Qualified or unqualified
1882 | QCONSYM { L1 $ mkQual dataName (getQCONSYM $1) }
1884 consym :: { Located RdrName }
1885 : CONSYM { L1 $ mkUnqual dataName (getCONSYM $1) }
1887 -- ':' means only list cons
1888 | ':' { L1 $ consDataCon_RDR }
1891 -----------------------------------------------------------------------------
1894 literal :: { Located HsLit }
1895 : CHAR { L1 $ HsChar $ getCHAR $1 }
1896 | STRING { L1 $ HsString $ getSTRING $1 }
1897 | PRIMINTEGER { L1 $ HsIntPrim $ getPRIMINTEGER $1 }
1898 | PRIMWORD { L1 $ HsWordPrim $ getPRIMWORD $1 }
1899 | PRIMCHAR { L1 $ HsCharPrim $ getPRIMCHAR $1 }
1900 | PRIMSTRING { L1 $ HsStringPrim $ getPRIMSTRING $1 }
1901 | PRIMFLOAT { L1 $ HsFloatPrim $ getPRIMFLOAT $1 }
1902 | PRIMDOUBLE { L1 $ HsDoublePrim $ getPRIMDOUBLE $1 }
1904 -----------------------------------------------------------------------------
1908 : vccurly { () } -- context popped in lexer.
1909 | error {% popContext }
1911 -----------------------------------------------------------------------------
1912 -- Miscellaneous (mostly renamings)
1914 modid :: { Located ModuleName }
1915 : CONID { L1 $ mkModuleNameFS (getCONID $1) }
1916 | QCONID { L1 $ let (mod,c) = getQCONID $1 in
1919 (unpackFS mod ++ '.':unpackFS c))
1923 : commas ',' { $1 + 1 }
1926 -----------------------------------------------------------------------------
1927 -- Documentation comments
1929 docnext :: { LHsDoc RdrName }
1930 : DOCNEXT {% case parseHaddockParagraphs (tokenise (getDOCNEXT $1)) of {
1931 MyLeft err -> parseError (getLoc $1) err;
1932 MyRight doc -> return (L1 doc) } }
1934 docprev :: { LHsDoc RdrName }
1935 : DOCPREV {% case parseHaddockParagraphs (tokenise (getDOCPREV $1)) of {
1936 MyLeft err -> parseError (getLoc $1) err;
1937 MyRight doc -> return (L1 doc) } }
1939 docnamed :: { Located (String, (HsDoc RdrName)) }
1941 let string = getDOCNAMED $1
1942 (name, rest) = break isSpace string
1943 in case parseHaddockParagraphs (tokenise rest) of {
1944 MyLeft err -> parseError (getLoc $1) err;
1945 MyRight doc -> return (L1 (name, doc)) } }
1947 docsection :: { Located (Int, HsDoc RdrName) }
1948 : DOCSECTION {% let (n, doc) = getDOCSECTION $1 in
1949 case parseHaddockString (tokenise doc) of {
1950 MyLeft err -> parseError (getLoc $1) err;
1951 MyRight doc -> return (L1 (n, doc)) } }
1953 moduleheader :: { (HaddockModInfo RdrName, Maybe (HsDoc RdrName)) }
1954 : DOCNEXT {% let string = getDOCNEXT $1 in
1955 case parseModuleHeader string of {
1956 Right (str, info) ->
1957 case parseHaddockParagraphs (tokenise str) of {
1958 MyLeft err -> parseError (getLoc $1) err;
1959 MyRight doc -> return (info, Just doc);
1961 Left err -> parseError (getLoc $1) err
1964 maybe_docprev :: { Maybe (LHsDoc RdrName) }
1965 : docprev { Just $1 }
1966 | {- empty -} { Nothing }
1968 maybe_docnext :: { Maybe (LHsDoc RdrName) }
1969 : docnext { Just $1 }
1970 | {- empty -} { Nothing }
1974 happyError = srcParseFail
1976 getVARID (L _ (ITvarid x)) = x
1977 getCONID (L _ (ITconid x)) = x
1978 getVARSYM (L _ (ITvarsym x)) = x
1979 getCONSYM (L _ (ITconsym x)) = x
1980 getQVARID (L _ (ITqvarid x)) = x
1981 getQCONID (L _ (ITqconid x)) = x
1982 getQVARSYM (L _ (ITqvarsym x)) = x
1983 getQCONSYM (L _ (ITqconsym x)) = x
1984 getPREFIXQVARSYM (L _ (ITprefixqvarsym x)) = x
1985 getPREFIXQCONSYM (L _ (ITprefixqconsym x)) = x
1986 getIPDUPVARID (L _ (ITdupipvarid x)) = x
1987 getCHAR (L _ (ITchar x)) = x
1988 getSTRING (L _ (ITstring x)) = x
1989 getINTEGER (L _ (ITinteger x)) = x
1990 getRATIONAL (L _ (ITrational x)) = x
1991 getPRIMCHAR (L _ (ITprimchar x)) = x
1992 getPRIMSTRING (L _ (ITprimstring x)) = x
1993 getPRIMINTEGER (L _ (ITprimint x)) = x
1994 getPRIMWORD (L _ (ITprimword x)) = x
1995 getPRIMFLOAT (L _ (ITprimfloat x)) = x
1996 getPRIMDOUBLE (L _ (ITprimdouble x)) = x
1997 getTH_ID_SPLICE (L _ (ITidEscape x)) = x
1998 getINLINE (L _ (ITinline_prag b)) = b
1999 getINLINE_CONLIKE (L _ (ITinline_conlike_prag b)) = b
2000 getSPEC_INLINE (L _ (ITspec_inline_prag b)) = b
2002 getDOCNEXT (L _ (ITdocCommentNext x)) = x
2003 getDOCPREV (L _ (ITdocCommentPrev x)) = x
2004 getDOCNAMED (L _ (ITdocCommentNamed x)) = x
2005 getDOCSECTION (L _ (ITdocSection n x)) = (n, x)
2007 getSCC :: Located Token -> P FastString
2008 getSCC lt = do let s = getSTRING lt
2009 err = "Spaces are not allowed in SCCs"
2010 -- We probably actually want to be more restrictive than this
2011 if ' ' `elem` unpackFS s
2012 then failSpanMsgP (getLoc lt) (text err)
2015 -- Utilities for combining source spans
2016 comb2 :: Located a -> Located b -> SrcSpan
2017 comb2 a b = a `seq` b `seq` combineLocs a b
2019 comb3 :: Located a -> Located b -> Located c -> SrcSpan
2020 comb3 a b c = a `seq` b `seq` c `seq`
2021 combineSrcSpans (getLoc a) (combineSrcSpans (getLoc b) (getLoc c))
2023 comb4 :: Located a -> Located b -> Located c -> Located d -> SrcSpan
2024 comb4 a b c d = a `seq` b `seq` c `seq` d `seq`
2025 (combineSrcSpans (getLoc a) $ combineSrcSpans (getLoc b) $
2026 combineSrcSpans (getLoc c) (getLoc d))
2028 -- strict constructor version:
2030 sL :: SrcSpan -> a -> Located a
2031 sL span a = span `seq` a `seq` L span a
2033 -- Make a source location for the file. We're a bit lazy here and just
2034 -- make a point SrcSpan at line 1, column 0. Strictly speaking we should
2035 -- try to find the span of the whole file (ToDo).
2036 fileSrcSpan :: P SrcSpan
2039 let loc = mkSrcLoc (srcLocFile l) 1 0;
2040 return (mkSrcSpan loc loc)